Sample failure: https://build.chromium.org/p/chromium.linux/builders/Linux%20Tests/builds/49565

[ RUN      ] DevToolsPixelOutputTests.TestLatencyInfoInstrumentation
Xlib:  extension "RANDR" missing on display ":99".
Xlib:  extension "RANDR" missing on display ":99".
[23559:23559:1201/092048.466508:WARNING:audio_manager.cc(317)] Multiple instances of AudioManager detected
[23559:23559:1201/092048.466535:WARNING:audio_manager.cc(278)] Multiple instances of AudioManager detected
[23559:23559:1201/092048.487136:WARNING:password_store_factory.cc(248)] Using basic (unencrypted) store for password storage. See https://chromium.googlesource.com/chromium/src/+/master/docs/linux_password_storage.md for more information about password storage options.
[23601:23601:1201/092048.596517:ERROR:sandbox_linux.cc(343)] InitializeSandbox() called with multiple threads in process gpu-process.
HTTP server started on http://127.0.0.1:49650...
sending server_data: {"host": "127.0.0.1", "port": 49650} (36 bytes)
[23559:23559:1201/092049.830303:ERROR:CONSOLE(57)] "Uncaught TypeError: Cannot read property 'addExtensions' of undefined", source: chrome-devtools://devtools/bundled/devtools_compatibility.js (57)
[23559:23559:1201/092050.408467:INFO:CONSOLE(1)] "DONE: waitForEvent.1", source:  (1)
[23559:23559:1201/092050.459953:INFO:CONSOLE(1)] "DONE: waitForEvent.2", source:  (1)
[23559:23559:1201/092050.465706:INFO:CONSOLE(1)] "DONE: waitForEvent.3", source:  (1)
[23559:23559:1201/092050.551117:INFO:CONSOLE(1)] "DONE: waitForEvent.4", source:  (1)
[23559:23559:1201/092050.633431:INFO:CONSOLE(1)] "DONE: waitForEvent.5", source:  (1)
[23559:23559:1201/092050.646327:INFO:CONSOLE(1)] "DONE: waitForEvent.6", source:  (1)
../../chrome/browser/devtools/devtools_sanity_browsertest.cc:140: Failure
Value of: result
  Actual: "[FAILED] Some expected events are not found: MouseDown"
Expected: "[OK]"
[  FAILED  ] DevToolsPixelOutputTests.TestLatencyInfoInstrumentation, where TypeParam =  and GetParam() =  (2897 ms)

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/ab777f3650bf6186cac2bc093966224ee3540f73

commit ab777f3650bf6186cac2bc093966224ee3540f73
Author: jbroman <jbroman@chromium.org>
Date: Thu Dec 01 18:22:33 2016

Skip DevToolsPixelOutputTests.TestLatencyInfoInstrumentation in site_per_process_browser_tests due to flakiness.

Doesn't seem similarly flaky on browser_tests, but further investigation is needed.

BUG= 670362 
TBR=lukasza@chromium.org
NOTRY=true

Review-Url: https://codereview.chromium.org/2538923004
Cr-Commit-Position: refs/heads/master@{#435652}

[modify] https://crrev.com/ab777f3650bf6186cac2bc093966224ee3540f73/testing/buildbot/filters/site-per-process.browser_tests.filter

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/5d92b307aa113179dc8cd87bbacce2f555d9ac02

commit 5d92b307aa113179dc8cd87bbacce2f555d9ac02
Author: Charles Reis <creis@chromium.org>
Date: Fri Oct 13 16:53:07 2017

Re-enable several browser_tests in --site-per-process mode.

BUG=417518, 671712, 669299,  670362 
TEST=Site Isolation FYI bots stay green

Cq-Include-Trybots: master.tryserver.chromium.linux:linux_site_isolation
Change-Id: Ic693f7adc5eb874a3ea5a0fef9e370a2ec79f7e9
Reviewed-on: https://chromium-review.googlesource.com/717943
Reviewed-by: Łukasz Anforowicz <lukasza@chromium.org>
Commit-Queue: Charlie Reis <creis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#508727}
[modify] https://crrev.com/5d92b307aa113179dc8cd87bbacce2f555d9ac02/testing/buildbot/filters/site-per-process.browser_tests.filter